Depending on the processed material from each drill must be properly sharpened. To verify the correct angle will help a specially prepared square plate of copper or aluminium with a thickness of 1 mm.
To become operational protractor enough to cut it cut, as shown in the picture: a large cutout at an angle of 120 degrees, the other half is 60 degrees and the surviving corner of a square is 90.
Recommend to read
IN THE LANGUAGE OF DOTS AND DASHES
It's tempting to assemble a simple Telegraph device and to communicate using Morse code. Reliable two-way communication is needed in the conduct of military sports games and...
“TRAP” IN THE SINK
I refused to offer the industry's trap — plastic perforated liner at the drain mouth of the shell: it has the shape of a hole and instantly get clogged even debris. Made of a plastic...
